Motorcycle handlebar assembly



FIG. 1 sets forth a perspective view of a motorcycle handlebar assembly showing the present invention new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a front view thereof; and,

FIG. 6 is a left side view thereof, the right side being a mirror image thereof.

The broken lines shown form no part of the claimed design. 

The ornamental design for a motorcycle handlebar assembly, as shown and described. 